How to save NLA action but don't use it?
There is a Muted checkbox in action strip properties. While in NLA editor hit N and open Active strip scroll (see wiki for more info). 



This exactly strip will no longer play while in animation.

Note that when Muted is turned on, it pauses on the current action of animation. So you might want to start animation again to make character return to his beginning position.

As another way it's possible to turn on Animated option in Evaluation scroll and set its value to 0.



The advantage is that the current position of character will be automatically set to beginning position when Alt+A pressed.